implements SMTP send an attachment

[coolmancool]

hello everyone..

i'm write a simple program that can send an email with an attachment.
so far, everything works fine, however, i don;t really understand why with
the following changes will make it doesn't work

[Before change ]
all the code is in java language. ( i use php tag to make the improve the readablity of them.)

String CRLF ="\r\n";
 
         SocketFactory socketFactory = SSLSocketFactory.getDefault();
         socket = socketFactory.createSocket("smtp.gmail.com", 465);
         in = new  BufferedReader(new   InputStreamReader(socket.getInputStream()));
         out = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
     
           //  HELO  Xmailerr
           //   AUTH login
           //  Data 
           //  from
           //  ................  
out.write("Mime-Version: 1.0");                     
out.write(CRLF);  out.flush();
out.write("Content-Type: multipart/mixed; "+CRLF +" boundary=\"" + boundary + "\""); 
out.write(CRLF); out.flush(); 
out.write(CRLF); out.flush();
   
        // text part
 
       // attachment part
            File file =  new File("Track3.mp3");
            out.write("--" + boundary); out.write(CRLF); out.flush();
            out.write("Content-Type: application/octet-stream; name="+  file.getName());     out.write(CRLF); out.flush();
            out.write("Content-Disposition: attachment;  filename=\""+file.getName()+"\""); out.write(CRLF); out.flush();
            out.write("Content-Transfer-Encoding: base64");                                 out.write(CRLF); out.flush();           
         
            out.write(CRLF);out.flush();
        // read the file  (i wanna to change above codes)
            FileInputStream fis = new FileInputStream(file);
            int av  = fis.available();
            byte bytes [] = new byte [av];
            fis.read(bytes);
            char chs [] = B64Code.encode(bytes);
            out.write(chs,0, chs.length); 
            
            out.write(CRLF); out.flush();
            out.write("--" + boundary + "--"); out.write(CRLF);out.flush();
            out.write(CRLF); out.write(".");  out.write(CRLF); out.flush();
            System.out.println((in.readLine());
            out.write("QUIT");
            out.flush(); 

after change
because i wanna send a very large of file ( 5mb) and i don;t want it load to memory at once..

 byte bytes [] = new byte [av];
           fis.read(bytes);
           char chs [] = B64Code.encode(bytes);
           out.write(chs,0, chs.length); 

since the above code that used to much memory if the file is large., then i decided to changed it to following code.

byte bytes [] = new byte [1024];
             int len = -1;
            while((len = fis.read(bytes,0, bytes.length)) > 0)
             {
               if(len == bytes.length){
                  char chs [] = B64Code.encode(bytes);
                  out.write(chs,0, chs.length);
                    }
               else{
                  byte b [] = new byte[len];
                  for(int i=0; i<len;i++)
                       b[i] = bytes[i];
                  char chs [] = B64Code.encode(b);
                  out.write(chs,0, chs.length); 
                 } 
            }
            out.write(CRLF); out.flush();
            out.write("--" + boundary + "--"); out.write(CRLF);out.flush();
            out.write(CRLF); out.write(".");  out.write(CRLF); out.flush();
            System.out.println((in.readLine());
            out.write("QUIT");
            out.flush(); 

after changed it , i tried to send another file, it no longer work for me,
i opend my gmail account, and checked the mail , it showed that only
1kb for the attachment,

however, I clicked "More Option, --- Show original" i can see the whole message that is encode in 64. not only 1kb..


thanks for you help in advance...

[coolmancool]

I know what cause the problem..

becouse i used a while loop, and it reads the byte [] is very fast...
and the newly readed byte [] will replace the previouse byte [] has not sent out..

i need some blocking method here....

can anyone tell me how to do that, make sure the previouse byte [] has write out, then write next byte []